MTFCA Forum

I have a spare generator for my 1922 T. I have tested it as I always do- with my drill and the generator in a vice. But this one only delivers electricity when it is spun anti-clockwise!
Battery neg. ground.
I have polarized several generators for people who want to change battery polarity( pos/neg ground). But I have never met a generator which only charges when turning the wrong way!
What have I done wrong - and how do I correct the odd problem?

There were repro field coils incorrectly wound - with those, you DID NOT cross the leads !

Reidar,

I can't walk on water but ...
I have seen it before twice. It were unknown generators I didn't work on before.
By one the field coils wires were not crossed. The other just needed to set the neutral right.

I did a rebuild on both after having found the problem and they never came back so I think they are OK.

Just my opinion.

Andre
Belgium

Are you sure it is not a Model A generator? Maybe the field coils are Model A? Otherwise, I don't know why it would be like that.

I have not found a generator like that, but have you checked for the null point by rotating the end plate so that when you hook to a battery, it will not run like a motor in either direction. this should be done with the third brush lifted When you set the brush end of the generator to the null point then lower and adjust the third brush so it will run like a motor.
Norm

Like RajoRacer said. Just swap the field coil leads and all should be good.

I will 3rd what Rajoracer said, also checking the null point. I had a generator that had those windings in it, had a devil of a time figuring it out.